#include<bits/stdc++.h>
using namespace std;
#define endl '\n'
typedef long long ll;
void solve(){
	ll n,m;cin>>n>>m;
	vector<ll> a(n+1);
	ll dian=0,xiaohao=0;
	for(ll i=1;i<=n;i++){
		cin>>a[i];
		dian+=a[i];
	}
	vector<pair<ll,ll>> v(n+1);
	for(ll i=1;i<=m;i++){
		cin>>v[i].first>>v[i].second;
	}
	sort(v.begin()+1,v.end());
	ll ans=dian;
	for(ll i=1;i<=n;i++){
		ll t=v[i].first-v[i-1].first;
		xiaohao+=t;
		if(dian>=t){
			dian-=t;
			ll tt=a[v[i].second];
			if(tt>=xiaohao){
				dian+=xiaohao;
				xiaohao=0;
			}else{
				dian+=tt;
				xiaohao-=tt;
			}
		}else{
			ans=v[i-1].first+dian;break;
		}
		if(i==n){
			ans=v[i].first+dian;break;
		}
	}
	cout<<ans<<endl;
	return;
}
int main(){
	ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	ll _;cin>>_;
	while(_--)solve();
	return 0;
}